Just curious....for those who have made diaper bags....what kind of interfacing did you use that seem to work well?

i'm having a hard time picking out just the right interfacing......i've used 2, one for the outer fabric, another one for the inner fabric (using mid-weight interfacing) and the bag is still a little too soft for me....

I finally got pics of my Jordy bags to share with everyone! Thanks to all for inspiring me to dust off my sewing machine! I've only been sewing for 6 months, so please be nice! But I do want your feedback! Thanks for letting me share! I'm having lots of fun making these Bags!!! - Marie